@mark_k:
Some emulators for Atari ST and Macintosh emulation just have the ROMs on their boards.
Once you have the ROMs dumped and you have found out the memory mapping, you should get them running easily.
Namely these emulation cards:

Atari ST emulators:• Maxon Chamäleon:
Atari ST emulator that runs Amiga OS and TOS exclusively (= not parallel) and does NOT emulate the Atari hardware registers and the Atari MIDI interface.This should be first implemented, as it is the simpliest Atari ST emulator.Link to Amiga Hardware Database

• Emplant:
The expansion board has several supporting Macintosh IC chips for the serial ports. There are several add-ons available for this board: an autobooting SCSI controller (NCR 53C80), Sybil - a hardware frequency synchronizer to handle 800 kB Mac floppy disks, e586 module for PC emulation.All these chips make it hard to emulate. But once you got the A-Max IV hardware running, this should be easier to emulate (they share same supporting Macintosh IC chips).Link to Amiga Hardware Database